Changes between Version 2 and Version 3 of PythonOcc

Timestamp:

Nov 28, 2011, 9:22:07 AM (14 years ago)

Author:

Leon Kos

Comment:

--

PythonOcc

@@ -26 +26 @@
     BaseClass = wx.glcanvas.GLCanvas
 }}}
+
+== Predstavitev CAD-jedra Open CASCADE na primerih ==
+=== Pregled uporabljenih OCC knjižnic ===
+{{{
+#!python
+## Importanje različnih knjižnic
+
+# Uporabniški vmesnik GUI
+from OCC.Display.SimpleGui import *
+
+# Matematična knjižnica
+import math
+
+# OpenCascade
+from OCC.gp import * #točke
+from OCC.BRepBuilderAPI import * #gradimo robove, segmente, mreže ...
+from OCC.BRepPrimAPI import * #izdelava osnovnih geometrijskih primitivov
+from OCC.BRepFilletAPI import * #izdelava zaokrožitev
+}}}
+
+Točnejša navodila, opis funkcij in knjižnic lahko dobimo v PythonOCC dokumentaciji.
+
+=== Inicializacija zaslona in izdelava grafičnega vmesnika===
+{{{
+#!python
+# OCC.Display.SimpleGui.init_display() returns multiple
+# values which are assigned here
+display, start_display, add_menu, add_function_to_menu = \
+init_display()
+draw_bottle() #kličemo CAD model, ki ga želimo prikazati na zaslonu
+start_display()
+}}}
+=== Risanje točk v prostoru ===
+Izdelava točk v prostoru je najosnovnejša operacija v OCC.
+{{{
+#!python
+# Definiranje začetnih točk
+aPnt1 = gp_Pnt(-myWidth / 2. , 0 , 0)
+aPnt2 = gp_Pnt(-myWidth / 2. , -myThickness / 4. , 0)
+aPnt3 = gp_Pnt(0 , -myThickness / 2. , 0)
+aPnt4 = gp_Pnt(myWidth / 2. , -myThickness / 4. , 0)
+aPnt5 = gp_Pnt(myWidth / 2. , 0 , 0)
+}}}
+
+=== Izdelava robnih elementov ===
+V naslednjem koraku se iz začetnih točk izdela robove:
+{{{
+#!python
+# Definiranje geometrije
+aArcOfCircle = GC_MakeArcOfCircle(aPnt2,aPnt3 ,aPnt4)
+aSegment1 = GC_MakeSegment(aPnt1 , aPnt2)
+aSegment2 = GC_MakeSegment(aPnt4 , aPnt5)
+
+# Definiranje topologije
+aEdge1 = BRepBuilderAPI_MakeEdge(aSegment1.Value())
+aEdge2 = BRepBuilderAPI_MakeEdge(aArcOfCircle.Value())
+aEdge3 = BRepBuilderAPI_MakeEdge(aSegment2.Value())
+}}}
+=== Povezovanje robnih elementov v mreže ===
+Robne elemente se v nadaljevanju združi v mrežo.
+{{{
+#!python
+# Izdelava mreže
+aWire  = BRepBuilderAPI_MakeWire(aEdge1.Edge() , aEdge2.Edge() ,aEdge3.Edge())
+}}}
+=== Uporaba funkcij za izdelavo objektov v prostoru ===
+{{{
+#!python
+# Izdelava celotnega profila - mirror
+xAxis = gp_OX()
+aTrsf = gp_Trsf()
+aTrsf.SetMirror(xAxis)
+aBRepTrsf = BRepBuilderAPI_Transform(aWire.Shape() , aTrsf)
+aMirroredShape = aBRepTrsf.Shape()
+aMirroredWire = TopoDS_wire(aMirroredShape)
+mkWire = BRepBuilderAPI_MakeWire()
+mkWire.Add(aWire.Wire())
+mkWire.Add(aMirroredWire)
+myWireProfile = mkWire.Wire()
+
+# Telo: Iz profila se izdela telo (Funkcija izvleka 3D)
+myFaceProfile = BRepBuilderAPI_MakeFace(myWireProfile)
+aPrismVec = gp_Vec(0 , 0 , myHeight)
+myBody = BRepPrimAPI_MakePrism(myFaceProfile.Face() , aPrismVec)
+}}}
+
+=== Risanje geometrijskih primitivov ===
+V OCC že obstajajo funkcije za izdelavo geometrijskih primitivov (kocka, valj,...), kar je prikazano na spodnjem primeru.
+{{{
+#!python
+from OCC.Display.SimpleGui import *
+from OCC.BRepPrimAPI import *
+
+display, start_display, add_menu, add_function_to_menu = init_display()
+my_box = BRepPrimAPI_MakeBox(10.,20.,30.).Shape()
+# ali my_cylinder = BRepPrimAPI_MakeCylinder(neckAx2 , myNeckRadius , myNeckHeight), kjer so spremenljivke že preddefinirane 
+
+display.DisplayShape(my_box) # ali display.DisplayShape(my_cylinder)
+start_display()
+}}}
+=== Izdelava primera Bottle z uporabo programskega jezika Python in knjižnice OCC ===
+Naslednji primer prikazuje izdelavo primera BottleCAD. Podrobnejši razdelek posameznih delov programske kode dobimo na [[http://trac.lecad.si/vaje/wiki/OpenCascade|MakeBottleCAD(C++)]].
+{{{
+#!python
+##Copyright 2011 Simon Kulovec (simon.kulovec@lecad.si)
+##Example: MakeCADBottle
+##This file is part of pythonOCC.
+
+## Importanje različnih knjižnic
+
+# Uporabniški vmesnik GUI
+from OCC.Display.SimpleGui import *
+
+# OpenCascade
+from OCC.gp import *
+from OCC.TopoDS import *
+from OCC.GC import *
+from OCC.BRepBuilderAPI import *
+from OCC.BRepPrimAPI import *
+from OCC.BRepFilletAPI import *
+from OCC.BRepAlgoAPI import *
+from OCC.Utils.Topology import *
+from OCC.Geom import *
+from OCC.Geom2d import *
+from OCC.GCE2d import *
+from OCC.BRep import *
+from OCC.BRepLib import *
+from OCC.BRepOffsetAPI import *
+from OCC.TopTools import *
+from OCC.TopAbs import *
+from OCC.TopExp import *
+
+import math
+
+def show_bottle(aRes):
+    display.EraseAll()
+    print dir(display)
+    display.DisplayShape(aRes)
+
+def define_points(myWidth, myThickness, myHeight):
+    #Definiranje začetnih točk
+    aPnt1 = gp_Pnt(-myWidth / 2. , 0 , 0)
+    aPnt2 = gp_Pnt(-myWidth / 2. , -myThickness / 4. , 0)
+    aPnt3 = gp_Pnt(0 , -myThickness / 2. , 0)
+    aPnt4 = gp_Pnt(myWidth / 2. , -myThickness / 4. , 0)
+    aPnt5 = gp_Pnt(myWidth / 2. , 0 , 0)
+
+    #Definiranje geometrije
+    aArcOfCircle = GC_MakeArcOfCircle(aPnt2,aPnt3 ,aPnt4)
+    aSegment1 = GC_MakeSegment(aPnt1 , aPnt2)
+    aSegment2 = GC_MakeSegment(aPnt4 , aPnt5)
+
+    #Definiranje topologije
+    aEdge1 = BRepBuilderAPI_MakeEdge(aSegment1.Value())
+    aEdge2 = BRepBuilderAPI_MakeEdge(aArcOfCircle.Value())
+    aEdge3 = BRepBuilderAPI_MakeEdge(aSegment2.Value())
+    aWire  = BRepBuilderAPI_MakeWire(aEdge1.Edge() , aEdge2.Edge() ,aEdge3.Edge())
+
+    #Izdelava celotnega profila - mirror
+    xAxis = gp_OX()
+    aTrsf = gp_Trsf()
+    aTrsf.SetMirror(xAxis)
+    aBRepTrsf = BRepBuilderAPI_Transform(aWire.Shape() , aTrsf)
+    aMirroredShape = aBRepTrsf.Shape()
+    aMirroredWire = TopoDS_wire(aMirroredShape)
+    mkWire = BRepBuilderAPI_MakeWire()
+    mkWire.Add(aWire.Wire())
+    mkWire.Add(aMirroredWire)
+    myWireProfile = mkWire.Wire()
+
+    # Telo: Iz profila se izdela telo
+    myFaceProfile = BRepBuilderAPI_MakeFace(myWireProfile)
+    aPrismVec = gp_Vec(0 , 0 , myHeight)
+    myBody = BRepPrimAPI_MakePrism(myFaceProfile.Face() , aPrismVec)
+
+    # Telo: Dodamo zaokrožitve (fillet)
+    mkFillet = BRepFilletAPI_MakeFillet(myBody.Shape())
+    topology_traverser = Topo(myBody.Shape())
+    for aEdge in topology_traverser.edges():
+        mkFillet.Add(myThickness / 12. , aEdge)
+    myBody = mkFillet.Shape()
+
+    #Dodajanje grla na steklenico
+    neckLocation = gp_Pnt(0, 0, myHeight)
+    neckNormal = gp_DZ()
+    neckAx2 = gp_Ax2(neckLocation, neckNormal)
+
+    myNeckRadius = myThickness / 4
+    myNeckHeight = myHeight / 10
+
+    mkCylinder = BRepPrimAPI_MakeCylinder(neckAx2 , myNeckRadius , \
+                                          myNeckHeight)
+    myNeck = mkCylinder.Shape();
+
+    myBody = BRepAlgoAPI_Fuse(myBody, myNeck)
+
+    # Izdelava votle steklenice
+    faceToRemove = None
+    zMax = -1;
+    t = Topo(myBody.Shape())
+    k=1
+    for  aFace in t.faces():
+    
+        aSurface = BRep_Tool().Surface(aFace)
+    
+        if aSurface.GetObject().IsInstance('Geom_Plane'):
+            aPlane = Handle_Geom_Plane().DownCast(aSurface).GetObject()
+            aPnt = aPlane.Location()
+            aZ = aPnt.Z()
+            if aZ>zMax:
+                faceToRemove = aFace
+
+    facesToRemove = TopTools_ListOfShape()
+    facesToRemove.Append(faceToRemove)
+    myBody = BRepOffsetAPI_MakeThickSolid(myBody.Shape() , facesToRemove , \
+                                          -myThickness/50 , 1.e-3)
+    
+    # Threading : Create Surfaces
+    aCyl1 = Geom_CylindricalSurface(gp_Ax3(neckAx2) , myNeckRadius * 0.99)
+    aCyl2 = Geom_CylindricalSurface(gp_Ax3(neckAx2) , myNeckRadius * 1.05)
+
+    # Threading : Define 2D Curves
+    aPnt = gp_Pnt2d(2. * 3.141592 , myNeckHeight / 2.)
+    aDir = gp_Dir2d(2. * 3.141592 , myNeckHeight / 4.)
+    aAx2d = gp_Ax2d(aPnt , aDir)
+        
+    aMajor = 2. * 3.141592
+    aMinor = myNeckHeight / 10.
+    
+    anEllipse1 = Geom2d_Ellipse(aAx2d , aMajor , aMinor)
+    anEllipse2 = Geom2d_Ellipse(aAx2d , aMajor , aMinor / 4)
+
+    aArc2 = Geom2d_TrimmedCurve(anEllipse1.GetHandle() , 3.141592, 0.)
+    aArc1 = Geom2d_TrimmedCurve(anEllipse2.GetHandle() , 3.141592, 0.)
+
+    anEllipsePnt2 = anEllipse1.Value(0.)
+    anEllipsePnt1 = anEllipse1.Value(3.141592)
+    
+    aSegment = GCE2d_MakeSegment(anEllipsePnt1 , anEllipsePnt2)
+
+    # Threading : Build Edges and Wires
+    aEdge1OnSurf1 = BRepBuilderAPI_MakeEdge(aArc1.GetHandle() , aCyl1.GetHandle())
+    aEdge2OnSurf1 = BRepBuilderAPI_MakeEdge(aSegment.Value() , aCyl1.GetHandle())
+    aEdge1OnSurf2 = BRepBuilderAPI_MakeEdge(aArc2.GetHandle() , aCyl2.GetHandle())
+    aEdge2OnSurf2 = BRepBuilderAPI_MakeEdge(aSegment.Value() , aCyl2.GetHandle())
+    print dir(aEdge1OnSurf1)
+    threadingWire1 = BRepBuilderAPI_MakeWire(aEdge1OnSurf1.Edge() , aEdge2OnSurf1.Edge())
+    threadingWire2 = BRepBuilderAPI_MakeWire(aEdge1OnSurf2.Edge() , aEdge2OnSurf2.Edge())
+
+
+    BRepLib().BuildCurves3d(threadingWire1.Wire())
+    BRepLib().BuildCurves3d(threadingWire2.Wire())
+
+    # Create Threading
+    aTool = BRepOffsetAPI_ThruSections(True)
+
+    aTool.AddWire(threadingWire1.Wire())
+    aTool.AddWire(threadingWire2.Wire())
+    aTool.CheckCompatibility(False)
+
+    myThreading = aTool.Shape()
+
+    # Izdelava sestava
+    aRes = TopoDS_Compound()
+
+    aBuilder = BRep_Builder()
+    aBuilder.MakeCompound (aRes)
+
+    aBuilder.Add (aRes, myBody.Shape())
+    aBuilder.Add (aRes, myThreading)
+
+    # Izris oblike
+    show_bottle(aPnt1)
+
+def draw_bottle(event=None):
+    # Definiranje razdalj: širina, dolžina, višina
+    myWidth = 50.0
+    myThickness = 30.0
+    myHeight = 70.0
+    # Define Points
+    define_points(myWidth, myThickness, myHeight)
+    
+if __name__ == '__main__':
+    # OCC.Display.SimpleGui.init_display() returns multiple
+    # values which are assigned here
+    display, start_display, add_menu, add_function_to_menu = \
+    init_display()
+    draw_bottle() #kličemo podprogram za izris bottle
+    start_display()
+}}}